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BACKGROUND: At present, the discovery of new biomarkers is of great significance for the early diagnosis, treatment and prognosis assessment of ovarian cancer. Previous findings indicated that aberrant G-protein-coupled receptor 176 (GPR176) expression might contribute to tumorigenesis and subsequent progression. However, the expression of GPR176 and the molecular mechanisms in ovarian cancer had not been investigated. METHODS: GPR176 expression was compared with clinicopathological features of ovarian cancer using immunohistochemical and bioinformatics analyses. GPR176-related genes and pathways were analysed using bioinformatics analysis. Additionally, the effects of GPR176 on ovarian cancer cell phenotypes were investigated. RESULTS: GPR176 expression positively correlated with elder age, clinicopathological staging, tumour residual status, and unfavourable survival of ovarian cancer, but negatively with purity loss, infiltration of B cells, and CD8+ T cells. Gene Set Enrichment Analysis showed that differential expression of GPR176 was involved in focal adhesion, ECM-receptor interaction, cell adhesion molecules and so on. STRING and Cytoscape were used to determine the top 10 nodes. Kyoto Encyclopaedia of Genes and Genomes analysis indicated that GPR176-related genes were involved in the ECM structural constituent and organisation and so on. GPR176 overexpression promoted the proliferation, anti-apoptosis, anti-pyroptosis, migration and invasion of ovarian cancer cells with overexpression of N-cadherin, Zeb1, Snail, Twist1, and under-expression of gasdermin D, caspase 1, and E-cadherin. CONCLUSION: GPR176 might be involved in the progression of ovarian cancer. It might be used as a biomarker to indicate the aggressive behaviour and poor prognosis of ovarian cancer and a target of genetic therapy.
Ovarian cancer is a gynecological cancer with high mortality. Due to the limited screening tests and treatments available, most ovarian cancer patients are diagnosed at a late stage and the prognosis is poor. The addition of new cancer diagnostic biomarkers and new intervention targets may improve quality of life and survival for patients with ovarian cancer. Previous studies have revealed the aberrant GPR176 expression might contribute to tumorigenesis and subsequent progression in many other tumours. In our study, GPR176 was found to promote the proliferation, anti-apoptosis, anti-pyroptosis, migration and invasion, EMT, and weakening the cellular adhesion of ovarian cancer cells, and involved in the Bcl-2/Bax or the PI3K/Akt/mTOR pathway. Therefore, abnormal expression of GPR176 might be served as a biomarker for aggressive behaviour and poor prognosis of ovarian cancer and a target for gene therapy.
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Neoplasias Ováricas , Receptores Acoplados a Proteínas G , Humanos , Femenino , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/terapia , Neoplasias Ováricas/patología , Neoplasias Ováricas/metabolismo , Persona de Mediana Edad , Terapia Genética/métodos , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Biología Computacional , Pronóstico , Proliferación Celular/genética , Carcinogénesis/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismoRESUMEN
JC polyoma virus (JCPyV), a ubiquitous polyoma virus that commonly infects people, is identified as the etiologic factor for progressive multifocal leukoencephalopathy and has been closely linked to various human cancers. Transgenic mice of CAG-loxp-Laz-loxp T antigen were established. T-antigen expression was specifically activated in gastroenterological target cells with a LacZ deletion using a cre-loxp system. Gastric poorly-differentiated carcinoma was observed in T antigen-activated mice using K19-cre (stem-like cells) and PGC-cre (chief cells), but not Atp4b-cre (parietal cells) or Capn8-cre (pit cells) mice. Spontaneous hepatocellular and colorectal cancers developed in Alb-cre (hepatocytes)/T antigen and villin-cre (intestinal cells)/T antigen transgenic mice respectively. Gastric, colorectal, and breast cancers were observed in PGC-cre/T antigen mice. Pancreatic insulinoma and ductal adenocarcinoma, gastric adenoma, and duodenal cancer were detected in Pdx1-cre/T antigen mice. Alternative splicing of T antigen mRNA occurred in all target organs of these transgenic mice. Our findings suggest that JCPyV T antigen might contribute to gastroenterological carcinogenesis with respect to cell specificity. Such spontaneous tumor models provide good tools for investigating the oncogenic roles of T antigen in cancers of the digestive system.
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Poliomavirus , Neoplasias Gástricas , Ratones , Humanos , Animales , Antígenos Virales de Tumores/genética , Ratones Transgénicos , Células Epiteliales/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologíaRESUMEN
FAM64A is a mitogen-induced regulator of the metaphase and anaphase transition. Here, we found that FAM64A messenger RNA (mRNA) and protein expression levels were higher in gastric cancer tissue than in normal mucosa (p < .05). FAM64A methylation was negatively correlated with FAM64A mRNA expression (p < .05). The differentially expressed genes of FAM64A were mainly involved in digestion, potassium transporting or exchanging ATPase, contractile fibers, endopeptidase, and pancreatic secretion (p < .05). The FAM64A-related genes were principally categorized into ubiquitin-mediated proteolysis, cell cycle, chromosome segregation and mitosis, microtubule binding and organization, metabolism of amino acids, cytokine receptors, lipid droplet, central nervous system, and collagen trimer (p < .05). FAM64A protein expression was lower in normal gastric mucosa than intestinal metaplasia, adenoma, and primary cancer (p < .05), negatively correlated with older age, T stage, lymphatic and venous invasion, tumor, node, metastasis stage, and dedifferentiation (p < .05), and associated with a favorable overall survival of gastric cancer patients. FAM64A overexpression promoted proliferation, antiapoptosis, migration, invasion, and epithelial-mesenchymal transition via the EGFR/Akt/mTOR/NF-κB, while the opposite effect was observed for FAM64A knockdown. FAM64A also induced chemoresistance directly or indirectly through lipid droplet formation via ING5. These results suggested that upregulation of FAM64A expression might induce aggressive phenotypes, leading to gastric carcinogenesis and its subsequent progression. Thus, FAM64A could be regarded as a prognosis biomarker and a target for gene therapy.
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Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Resistencia a Antineoplásicos/genética , Gotas Lipídicas/metabolismo , Gotas Lipídicas/patología , Regulación Neoplásica de la Expresión Génica , Biomarcadores , Proliferación Celular/genética , ARN Mensajero , Terapia Genética , Línea Celular Tumoral , Movimiento Celular , PronósticoRESUMEN
Gastric cancer remains one of the most prevalent and lethal malignancies in the world. Despite new advances in treatment and diagnosis, patients with advanced gastric cancer are still difficult to cure resulting in a high mortality rate and poor prognosis. Signal transducer and activator of transcription 3 (Stat3) is observed aberrant in multiple tumours, including gastric cancer. Stat3 overexpression was confirmed performing a vital role in tumorigenesis. In the present study, we constructed a pSi-Stat3 plasmid to silence Stat3 and investigated the effect of pSi-Stat3 on cell proliferation, apoptosis and cell cycle progression in gastric cancer cell line SGC-7901 and mice xenograft model. Downstream proteins of Stat3, including Cyclin-D1, Survivin and Bcl-2, were detected as well for the underlying mechanism exploration. It showed that pSi-Stat3 can effectively silence the expression of Stat3 and inhibits the growth of gastric tumour both in vitro and in vivo significantly via cell apoptosis and cell cycle shift induction. The findings suggest that Stat3 signal pathway might be a promising therapeutic target for tumour treatment, including gastric cancer.
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Antineoplásicos/farmacología , ARN Interferente Pequeño/farmacología , Factor de Transcripción STAT3/antagonistas & inhibidores , Neoplasias Gástricas/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular , Línea Celular Tumoral , Ciclina D1/metabolismo , Femenino , Genes bcl-2 , Xenoinjertos , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Mensajero/antagonistas & inhibidores , Factor de Transcripción STAT3/genética , Neoplasias Gástricas/metabolismo , SurvivinRESUMEN
Keratin 80 (KRT80) is a filament protein that makes up one of the major structural fibers of epithelial cells, and involved in cell differentiation and epithelial barrier integrity. Here, KRT80 mRNA expression was found to be higher in esophageal cancer than normal epithelium by RT-PCR and bioinformatics analysis (p < .05), opposite to KRT80 methylation (p < .05). There was a negative relationship between promoter methylation and expression level of KRT80 gene in esophageal cancer (p < .05). KRT80 mRNA expression was positively correlated with the differentiation, infiltration of immune cells, and poor prognosis of esophageal cancer (p < .05). KRT80 mRNA expression was positively linked to no infiltration of immune cells, the short survival time of esophageal cancers (p < .05). The differential genes of KRT80 mRNA were involved in fat digestion and metabolism, peptidase inhibitor, and intermediate filament, desosome, keratinocyte differentiation, epidermis development, keratinization, ECM regulator, complement cascade, metabolism of vitamins and co-factor (p < .05). KRT-80-related genes were classified into endocytosis, cell adhesion molecule binding, cadherin binding, cell-cell junction, cell leading edge, epidermal cell differentiation and development, T cell differentiation and receptor complex, plasma membrane receptor complex, external side of plasma membrane, metabolism of amino acids and catabolism of small molecules, and so forth (p < .05). KRT80 knockdown suppressed anti-apoptosis, anti-pyroptosis, migration, invasion, chemoresistance, and lipogenesis in esophageal cancer cells (p < .05), while ACC1 and ACLY overexpression reversed the inhibitory effects of KRT80 on lipogenesis and chemoresistance. These findings indicated that up-regulated expression of KRT80 might be involved in esophageal carcinogenesis and subsequent progression, aggravate aggressive phenotypes, and induced chemoresistance by lipid droplet assembly and ACC1- and ACLY-mediated lipogenesis.
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Resistencia a Antineoplásicos , Neoplasias Esofágicas , Queratinas Tipo II , Humanos , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Resistencia a Antineoplásicos/genética , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/genética , Regulación Neoplásica de la Expresión Génica , Lipogénesis/genética , ARN Mensajero , Queratinas Tipo II/genética , Queratinas Tipo II/metabolismoRESUMEN
Hepatocellular carcinoma (HCC) has become a severe burden on global health due to its high morbidity and mortality rates. However, effective treatments for HCC are limited. The lack of suitable preclinical models may contribute to a major failure of drug development for HCC. Here, we overview several well-established mouse models of HCC, including genetically engineered mice, chemically-induced models, implantation models, and humanized mice. Immunotherapy studies of HCC have been a hot topic. Therefore, we will introduce the application of mouse models of HCC in immunotherapy. This is followed by a discussion of some other models of HCC-related liver diseases, including non-alcoholic fatty liver disease (NAFLD), hepatitis B and C virus infection, and liver fibrosis and cirrhosis. Together these provide researchers with a current overview of the mouse models of HCC and assist in the application of appropriate models for their research.
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BACKGROUND: Belonging to the G-protein coupled receptor 1 family, G protein-coupled receptor 176 (GPR176) is associated with the Gz/Gx G-protein subclass and is capable of decreasing cAMP production. METHODS: GPR176 expression was detected by qRT-PCR, bioinformatics analysis, Western blot and immunohistochemistry, and compared with clinicopathological characteristics of breast cancer. GPR176-related genes and pathways were subjected to bioinformatic analysis. We also explored the effects of GPR176 on the phenotypes of breast cancer cells. RESULTS: Lower expression of GPR176 mRNA was seen in breast cancer than in normal tissues, but the opposite pattern was found for its protein (p < 0.05). GPR176 mRNA was associated with female sex, low T staging, non-Her-2+ subtypes, non-mutant p53 status in breast cancer (p < 0.05). GPR176 methylation was negatively correlated with its mRNA level and T staging in breast cancer, and was higher in breast cancer than normal tissues (p < 0.05). GPR176 protein expression was positively correlated with older age, small tumor size, and non-luminal-B subtype of breast cancers (p < 0.05). The differential genes of GPR176 were involved in receptor-ligand interaction, RNA maturation, and so forth (p < 0.05). GPR176-related genes were categorized into cell mobility, membrane structure, and so on (p < 0.05). GPR176 knockdown weakened the proliferation, glucose catabolism, anti-apoptosis, anti-pyroptosis, migration, invasion, and epithelial-mesenchymal transition of breast cancer cells. CONCLUSION: These results indicate that GPR176 might be involved in the tumorigenesis and subsequent progression of breast cancer by deteriorating aggressive phenotypes. It might be utilized as a potential biomarker to indicate the aggressive behaviors and poor prognosis of breast cancer and a potential target of genetic therapy.
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Terapia Genética , Neoplasias , Femenino , Animales , Biomarcadores , Movimiento Celular/genética , Fenotipo , ARN Mensajero/genética , Regulación Neoplásica de la Expresión Génica , Proliferación Celular , Línea Celular Tumoral , Pronóstico , Neoplasias/genéticaRESUMEN
PURPOSE: As a member of the G-protein-coupled receptor 1 family, the G-protein-coupled receptor 176 (GPR176) gene encodes a glycosylated protein made up of 515 amino acids. The current study was performed to evaluate the impact of GPR176 on the clinicopathology and prognosis of oesophageal cancer, as well as uncover its molecular mechanisms. METHODS: Bioinformatics and clinical tissue samples were used to detect the expression and clinicopathological significance of GPR176 in oesophageal cancer. The expression, proliferation, migration and invasion, apoptosis and lipid droplet formation of GPR176 gene in oesophageal cancer were performed as phenotypic readouts. RESULTS: Here, RT-PCR and bioinformatic analyses revealed that GPR176 mRNA expression was significantly higher in oesophageal cancer than in normal mucosa (p < 0.05). GPR176 mRNA expression was associated with low weight and BMI, low T stage, low N and clinicopathological stage, low histological grade and favourable clinical outcome of oesophageal cancer (p < 0.05). The differential genes of GPR176 mRNA were involved in protein digestion and absorption, extracellular matrix constituent, endoplasmic reticulum lumen, among others (p < 0.05). GPR176-related genes were classified as being involved in oxidoreductase activity, actin and myosin complexes, lipid localisation and transport, among others (p < 0.05). GPR176 knockdown suppressed proliferation, anti-apoptotic and anti-pyroptotic properties, migration, invasion, chemoresistance and lipid droplet formation in oesophageal cancer cells (p < 0.05), while ACC1 and ACLY overexpression reversed the inhibitory effects of GPR176 silencing on lipid droplet formation and chemoresistance. CONCLUSION: These findings indicated that upregulated expression of GPR176 might be involved in oesophageal carcinogenesis and subsequent progression, aggressiveness, and induced chemoresistance by ACC1- and ACLY-mediated lipogenesis and lipid droplet assembly.
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Neoplasias Esofágicas , Lipogénesis , Humanos , Resistencia a Antineoplásicos/genética , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Proliferación Celular , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , ARN Mensajero/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión GénicaRESUMEN
Grin2d is an ionotropic NMDA receptor, a subunit of glutamate-dependent, and a facilitator of cellular calcium influx in neuronal tissue. In this study, we found that Grin2d expression was higher in esophageal cancer than in normal mucosa at both the mRNA and protein level using RT-PCR, bioinformatics analysis, and western blotting (p<0.05). Grin2d mRNA expression was positively correlated with old age, white race, heavy weight, distal location, adenocarcinoma, cancer with Barrett's lesion, or high-grade columnar dysplasia (p<0.05). The differential genes associated with Grin2d mRNA were involved in fat digestion and absorption, cholesterol metabolism, lipid transfer, lipoproteins, synaptic membranes, and ABC transporters (p<0.05). The Grin2d-related genes were classified into the following categories: metabolism of glycerolipids, galactose, and O-glycan, cell adhesion binding, actin binding, cadherin binding, the Hippo signaling pathway, cell-cell junctions, desmosomes, DNA-transcription activator binding, and skin development and differentiation (p<0.05). Grin2d immunoreactivity was positively correlated with distal metastasis and unfavorable overall survival in esophageal cancer (p<0.05). Grin2d overexpression promoted proliferation, migration, and invasion in esophageal cancer cells but blocked apoptosis (p<0.05) and increased the expression of PI3K, Akt and p-mTOR. Grin2d knockout caused the opposite effects. These findings indicated that upregulated Grin2d expression played an important role in esophageal carcinogenesis via the PI3K/Akt/mTOR pathway and might be a biological marker for aggressive tumor behavior and poor prognosis. Its silencing might represent a targeted therapy approach against esophageal cancer.
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OBJECTIVE: Brain magnetic resonance imaging (MRI) findings in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis are nonspecific and rarely have obvious associations with clinical characteristics and outcomes. This study aimed to comprehensively describe the MRI features of patients with NMDAR encephalitis, examine their associations with clinical characteristics, and evaluate their predictive power for disease recurrence and prognosis. METHODS: We retrospectively extracted the clinical data and brain MRI findings of 144 patients with NMDAR encephalitis. Patients underwent a 2-year follow-up to assess disease outcomes. We evaluated the associations of brain MRI findings at the onset with clinical characteristics, recurrence, and prognosis. RESULTS: Initial MRI showed typical abnormalities in 65 patients (45.1%); of these, 34 (29.3%) developed recurrence and 10 (9.4%) had poor prognosis (mRS ≥3). Binary logistic regression analyses revealed that insula abnormalities were associated with acute seizure (odds ratio [OR] = 3.048, 95% confidence interval [CI]: 1.026-9.060) and white matter lesions were associated with cognitive impairment (OR = 2.730, 95% CI: 1.096-6.799). Risk factors for a poor 2-year prognosis included a higher number of brain MRI abnormalities (OR = 1.573, 95% CI: 1.129-2.192) and intensive care unit (ICU) admissions (OR = 15.312, 95% CI: 1.684-139.198). The risk factors for 2-year recurrence included abnormalities of the thalamus (HR = 3.780, 95% CI: 1.642-8.699). INTERPRETATIONS: Brain MRI features of patients with NMDAR encephalitis were associated with clinical manifestations, prognosis, and recurrence. Higher numbers of MRI abnormalities and ICU admissions were predictive of poor prognosis. Abnormalities of the thalamus constituted a recurrence-related risk factor.
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Encefalitis Antirreceptor N-Metil-D-Aspartato , Encefalopatías , Humanos , Encefalitis Antirreceptor N-Metil-D-Aspartato/diagnóstico por imagen , Estudios Retrospectivos , Recurrencia Local de Neoplasia , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Receptores de N-Metil-D-AspartatoRESUMEN
OBJECTIVE: The objective of this study was to perform a meta-analysis comparing the efficiency of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) with chemotherapy to EGFR TKI treatment alone in patients with EGFR mutation-positive non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Following keyword queries in databases and identification of randomized control trials for inclusion, hazard ratios (HRs), relative risks (RRs), and associated 95% confidence intervals (95% CIs) were determined. RESULTS: Ten randomized controlled trials involving 1354 participants with NSCLC were evaluated. We found that a combined approach of chemotherapy with EGFR TKIs significantly improved overall survival (OS) compared with EGFR TKI alone in our patient cohort (HR = 0.47, 95% CI = 0.31-0.72). In addition, a higher overall response rate (ORR) was found for patients who received combined treatment compared to chemotherapy alone (RR = 2.17, 95% CI = 1.51-3.12). Furthermore, concomitant use of chemotherapy with TKIs significantly improved the progression-free survival (PFS) when compared to the use of TKIs alone (HR = 0.68, 95% CI = 0.49-0.95). Moreover, there was a higher ORR among patients who received combined treatment as compared to those who were managed using TKIs only (RR=1.17, 95%CI=1.09-1.25). CONCLUSION: Our meta-analysis shows that EGFR TKIs with chemotherapy confer better OS and ORR compared to either treatment alone, similarly, the combined treatment showed better PFS and ORR profiles than the use of TKI alone.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Mutación , Supervivencia sin Progresión , Inhibidores de Proteínas Quinasas/farmacología , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Background Belonging to the G-protein coupled receptor 1 family, G protein-coupled receptor 176 (GPR176) is associated with the Gz/Gx G-protein subclass and is capable of decreasing cAMP production. Methods GPR176 expression was detected by qRT-PCR, bioinformatics analysis, Western blot and immunohistochemistry, and compared with clinicopathological characteristics of breast cancer. GPR176-related genes and pathways were subjected to bioinformatic analysis. We also explored the effects of GPR176 on the phenotypes of breast cancer cells. Results Lower expression of GPR176 mRNA was seen in breast cancer than in normal tissues, but the opposite pattern was found for its protein (p < 0.05). GPR176 mRNA was associated with female sex, low T staging, non-Her-2+ subtypes, non-mutant p53 status in breast cancer (p < 0.05). GPR176 methylation was negatively correlated with its mRNA level and T staging in breast cancer, and was higher in breast cancer than normal tissues (p < 0.05). GPR176 protein expression was positively correlated with older age, small tumor size, and non-luminal-B subtype of breast cancers (p < 0.05). The differential genes of GPR176 were involved in receptor-ligand interaction, RNA maturation, and so forth (p < 0.05). GPR176-related genes were categorized into cell mobility, membrane structure, and so on (p < 0.05). GPR176 knockdown weakened the proliferation, glucose catabolism, anti-apoptosis, anti-pyroptosis, migration, invasion, and epithelial-mesenchymal transition of breast cancer cells. Conclusion These results indicate that GPR176 might be involved in the tumorigenesis and subsequent progression of breast cancer by deteriorating aggressive phenotypes. It might be utilized as a potential biomarker to indicate the aggressive behaviors and poor prognosis of breast cancer and a potential target of genetic therapy (AU)
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Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Terapia Genética , Regulación Neoplásica de la Expresión Génica , ARN Mensajero/genética , Biomarcadores de Tumor , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Pronóstico , FenotipoRESUMEN
BACKGROUND: MiRNA primarily acts to repress gene expression at the post-transcriptional level through imperfect complementarity of its 5' region to the "seed site" in the 3' untranslated region of target mRNAs, with its "3'-supplementary site" and "center site" also playing important roles under certain circumstances. The aim of this study was to test if artificial miRNA mimics (miR-Mimics) that are designed to target the "centered sites" without "seed sites" complementarity are able to repress gene expression as natural miRNAs. METHODS: We designed miR-Mimics carrying centered-site matches (CS-miR-Mimics) or seed-site matches (SS-miR-Mimics) and siRNA to two antiapoptotic genes BCL2 and AKT1. We tested the gene targeting of these constructs using real-time RT-PCR and Western blot to quantify mRNA and protein levels of BCL2 and AKT1, respectively, luciferase reporter gene assay to investigate the interaction between miR-Mimics and their target sites, and cell survival assay to study the functional outcomes of the miR-Mimics. RESULTS: We found that CS-miR-Mimic, SS-miR-Mimic and siRNA, all down regulated the mRNA and protein levels of their cognate target BCL2 or AKT1 in a concentration-dependent manner. Luciferase reporter gene assay further confirmed the functional interactions of CS-miR-Mimic, SS-miR-Mimic and siRNA with their target sites. We then observed that the miR-Mimics and siRNAs were all able to induce cell death, as indicated by the reduced survival rate of cells. CONCLUSIONS: We have provided evidence for the feasibility of CS-miR-Mimics for post-transcriptional repression of genes, which can be designed to have reduced numbers of seed type off-target sites compared to the number of target sites from an average endogenous seed-site miRNA. CS-miR-Mimics may be a novel approach for miRNA research requiring miRNA gain-of-function.